Customcontrol in Asp.net

Designing a customcontrol as simple as designing a user control in asp.net, and more fun, once you create a custom control you can use in any other project which is not posssible in user control.

Let's start with baby step
Add a class file with name "MyCustomControl.cs" & add this namespace
using System.ComponentModel;

Now inherit the class from System.Web.UI.WebControls.WebControl,INamingContainer

Design customcontrol in asp.net

using System; 1:using System.Web.UI; 2:using System.Web.UI.WebControls; 3:using System.ComponentModel; 4:using System.Text; 5:using System.IO; 6: 7:namespace Arindam 8:{ 9: 10: [DefaultProperty("Text"), 11: ToolboxData("<{0}:CodeContainer runat=server></{0}:CodeContainer>")] 12: public class MyCustomControl: System.Web.UI.WebControls.WebControl,INamingContainer 13: { 14: 15: string _clientScriptPath = ""; 16: 17: override protected void OnInit(EventArgs e) 18: { 19: this._clientScriptPath = "Set any property value as per your need"; 20: Intialize(); 21: } 22: 23: 24: private void Intialize() 25: { 26: 27: this.Load += new EventHandler(CodeContainer_Load); 28: } 29: 30: 31: protected void CodeContainer_Load(object source, EventArgs e) 32: { 33: // here you write code what your control to do while loading. 34: } 35: } 36:} 37:

You can add any number of child controls in in your costom control, you also can set the rendering order as per your need.

override CreateChildControls() in customcontrol in asp.net

using System; 1:using System.Web.UI; 2:using System.Web.UI.WebControls; 3:using System.ComponentModel; 4:using System.Text; 5:using System.IO; 6: 7:namespace Arindam 8:{ 9: 10: [DefaultProperty("Text"), 11: ToolboxData("<{0}:CodeContainer runat=server></{0}:CodeContainer>")] 12: public class MyCustomControl: System.Web.UI.WebControls.WebControl,INamingContainer 13: { 14: string _clientScriptPath = ""; 15: Panel objPanel; 16: Literal objLtrl; 17: Label objLab; 18: 19: protected override void CreateChildControls() 20: { 21: 22: objPanel=new Panel(); 23: objLtrl=new Literal (); 24: objLab=new Label(); 25: 26: objPanel.ID ="CodeZone"; 27: 28: objLab.Text = this.Title; 29: 30: objLab.Font.Bold = true; 31: objLab.BorderWidth = Unit.Pixel(1); 32: objLab.BorderStyle = BorderStyle.Dotted; 33: objLab.BorderColor = System.Drawing.Color.FromName("#A0A0A1"); 34: // int _imgwidth = objImg == null ? 0 : (int)objImg.Width; 35: objLab.Width = Unit.Pixel(this.AreaWidth - 14); 36: objLtrl.Text = this.Text ; 37: 38: objPanel.BackColor = System.Drawing.Color.Cornsilk ; 39: objPanel.Height = Unit.Pixel(this.AreaHeight) ; 40: objPanel.Width = Unit.Pixel(this.AreaWidth) ; 41: objPanel.BorderWidth = Unit.Pixel(1); 42: objPanel.Controls.Add(objLtrl); 43: 44:// set rendering order here . 45: Controls.Add(objImg); 46: Controls.Add(objLab); 47: Controls.Add(objPanel); 48: 49: 50: 51: base.CreateChildControls (); 52: } 53: } 54:} 55:

Now see how to create properties in customcontrol

override CreateChildControls() in customcontrol in asp.net

using System; 1:using System.Web.UI; 2:using System.Web.UI.WebControls; 3:using System.ComponentModel; 4:using System.Text; 5:using System.IO; 6: 7:namespace Arindam 8:{ 9: 10: [DefaultProperty("Text"), 11: ToolboxData("<{0}:CodeContainer runat=server></{0}:CodeContainer>")] 12: public class MyCustomControl: System.Web.UI.WebControls.WebControl,INamingContainer 13: { 14: string _filePath; 15: 16: 17: /// <summary> 18: /// sample : RootFolder\SubFolder\file.cs,.sql,.xml etc 19: /// </summary> 20: [Bindable(true), 21: Category("Appearance"), 22: DefaultValue("")] 23: public string FilePath 24: { 25: get 26: { 27: return _filePath; 28: } 29: 30: set 31: { 32: _filePath = value; 33: } 34: } 35: 36: } 37:} 38: